Circulation enhancement boots have been known in the art for some period of time. One such boot is known as a “Circulator Boot,” has been available for several years. This boot is used to compress an extremity between 1–3 milliseconds after the QRS segment of the heart beat. By doing so, the superficial fluid in the leg is pumped back into the circulatory path. The pressure from the heart is at its lowest point when compression occurs. Therefore, by squeezing fluids back to the heart it not only aids in increasing heart flow and profusion to the heart; but also, by emptying the superficial veins and fluid in the leg, the pressure from the heart helps to push fresh blood into the extremity.
The following prior art discloses the various aspects in the design and use of the peripheral circulation enhancement system.
U.S. Pat. No. 5,458,562, granted Oct. 17, 1995, to G. F. Cooper, discloses an apparatus where blood circulation in an injured human foot is involuntarily promoted in a vacuum over-pressure cycle and in synchronism with the heart's systolic and diastolic pressure pulsations. In a preferred embodiment the circulation apparatus comprises an air tight boot contoured to the injured foot, a pulsed synchronized tourniquet for inhibiting blood flow to the injured foot during an over-pressure cycle and a control circuit which monitors the heart's systolic and diastolic pressure pulsations and provides electrical control signals to the pressure modulator to assure that the over-pressure and vacuum pulses are cyclic and in synchronism with the heart's systolic and diastolic pressure pulsations.
U.S. Pat. No. 5,514,079, granted May 7, 1996, to R. S. Dillon, teaches of a method and apparatus for improving the circulation of blood through a patient's heart and extremity. The method comprises applying external positive regional pressure on an extremity synchronously with the patient's heartbeat. An adjustable timing cycle is initiated at the QRS complex of the arterial pulse cycle. The timing cycle is based on an average time period between QRS complexes, which is calculated from a measurement of several successive QRS complexes in the patient's heart rate. Pressure pulses are applied in the end-diastolic portion of the arterial pulse cycle to reinforce the pulse that forces blood into the extremity. The pressure is then relieved prior to the next projected QRS complex to enable the next pulse to enter the extremity without undue obstruction, thereby promoting circulation of blood through the extremity. To promote circulation of blood through the heart, compression of the extremity is released shortly before the next projected QRS complex.
U.S. Pat. No. 5,674,262, granted Oct. 7, 1997, to D. M. Tumey, discloses a device and method for stimulating blood flow velocity in a leg of the body for the prevention of Deep Vein Thrombosis in an effective and relatively painless manner which, in one case, includes an apparatus for compressing a foot in a manner to drive a substantial amount of blood from veins of the foot therein into blood vessels of the leg and an apparatus operably associated with the compressing apparatus for electrically stimulating leg muscles as the driven blood from the foot passes through, such that the muscles drivingly enhance blood flow velocity.
With reference to Dillon, the heart monitor for Circulator Boot (CB) functions by utilizing the QRS segment of the heart beat which is ventricular contraction. It functions by triggering the compression at about 1–3 milliseconds after diastole. The CB uses a hard fiberglass shell with a specialized plastic air bag inside the shell. There is a Velcro sleeve around the extremity to control the outward expansion of the plastic air bag. This forces the plastic airbag to force its pressure inward. Also, the CB controller is mounted on top of the fiberglass housing. An “O” ring hooks to the underside of the valve directly. When the heart monitor opens the valve, a quick surge of air is forced into the plastic bag, and the valve releases to vent the entrapped air. Thus, the cycle is very rapid and in about one second the air compresses the extremity.
What is needed is circulation enhancement system that initiates the compression cycle by sensing when the heart reaches the “P” segment, and then slowly increases the applied pressure, compressing the extremity, until the back pressure from the heart is near the lowest point, thereby relieving the pressure while anticipating the next cycle. In this regard, the present invention fulfils this need.
It is therefore an object of the present invention to provide a peripheral circulation enhancement system that utilizes a heart monitor to observe a patient's heartbeat.
It is another object of the present invention to provide a peripheral circulation enhancement system that utilizes a heart monitor to observe a patient's heartbeat to sense the “P” segment of the heart wave.
It is still another object of the present invention to provide a peripheral circulation enhancement system that utilizes a heart monitor to observe a patient's heartbeat to sense the “P” segment of the heart wave and to count every beat, every second beat or every third beat.
It is still yet another object of the present invention to provide a peripheral circulation enhancement system that utilizes a heart monitor to observe a patient's heartbeat to sense the “P” segment of the heart wave and when the selected number of beats is attained, initiate the compression cycle.
Another object of the present invention is to provide a peripheral circulation enhancement system that utilizes a heart monitor to observe a patient's heartbeat to sense the “P” segment of the heart wave and when diastole is reached, being the lowest pressure from the heart, the internal pressure within the boot is slowly decreased by allowing the entrapped air to be released to the ambient.
Still another object of the present invention is to provide a peripheral circulation enhancement system that utilizes a double wall formed boot, having an expandable spandex-like material inside and an outer membrane of a formed soft flexible plastic.
A final object of the present invention is to provide a peripheral circulation enhancement system that utilizes a controller having two flow regulators, one to control the slowly increasing volume of air entering the compression boot, and one to control the slow release of the air entrapped within the compression boot.